The Biggest Loser Australia 2006 winner Adro Sarnelli and the show's former host Ajay Rochester are embroiled in a war of words after a heated online exchange at the weekend.
It all started when Adro, now a personal trainer, called Ajay "massive" on a Facebook forum while criticising overweight people who struggle to change their habits and slim down.
Ajay, who appeared on the Nine Network weight-loss reality show Excess Baggage earlier this year, responded to Adro on her blog, Fingingmymojo.com, with a fiery attack.
"Adro, I have found your comments disgusting, pathetic and sad," the 43-year-old wrote.
"Adro, you of all people should understand that weight loss and weight gain holds many issues and to call overweight people pathetic, lazy, drug addicts that you have 'minor compassion' for shows that you truly do not understand the true and everlasting depths and struggles of obesity."
Ajay claimed that Adro came to the show as a "lost, broken, desperate, powerless father".
She went on to claim that contestants asked her to get producers to drug test him at his final weigh-in, and that he also "begged" for her support while creating his own weight loss camp after the show ended.
The Biggest Loser winner, who runs an obesity rehab clinic in Melbourne, responded to Ajay's rant in the Sydney Morning Herald.
"She has made some pretty ridiculous allegations here … I made a mistake of using the word 'massive', which I probably shouldn't have," he told the newspaper.
"But the point I was making was that it's a shame Ajay hasn't been able to keep the weight off ... I know as much as anyone how frustrating it can be.
"I guess it was Ajay's victim mentality I was referring to. You have to get past that if you really want to make changes."
Ajay, who has a child with ex-husband Martin Gleave, was photographed recently getting intimate on a Malibu beach with a brunette (see pic above).
In pics: Australia's trashiest reality TV shows